Die and punch assembly for compacting powder and method of assembly

ABSTRACT

A die and punch assembly for use on a powder compacting press for making articles compacted from a powder and a method of assembly. The assembly comprises a die plate appropriately mounted to the press and includes an aperture in which a die bushing is adhesively bonded, the die bushing having one or more cavities, each of which has a punch slidably and snugly disposed therein. The punches are collectively actuated by a common punch support which is in turn carried by a pair of posts extending below the die plate to permit reciprocal movement of the punches within their respective die cavities. A plurality of core rods are provided, with each punch having one end of at least one core rod disposed within a longitudinal bore formed in each punch, while the other end of said core rod is fixedly mounted on a core rod support, which in turn is fixedly mounted to the posts below the punch support. Means disposed below the core rod support and extending therethrough are operatively connected to the punch support to selectively cause reciprocation thereof.

United States Patent [151 3,640,654

Smith [451 Feb. 8, 1972 [54] DIE AND PUNCH ASSEMBLY FOR COMPACTING POWDER AND METHOD OF ASSEMBLY Primary Examiner-J. Howard Flint, Jr. Attorney-Hauke, Gifiord and Patalidis [72] Inventor: Joseph E. Smith, Birmingham, Mich. [57] ABSTRACT [73] Assignee: Wolverine-Pentronix, lnc., Lincoln Park, A die and punch assembly for use on a powder compacting Mi h press for making articles compacted from a powder and a method of assembly. The assembly comprises a die plate ap- [22] Flled' June 1970 propriately mounted to the press and includes an aperture in [2]] Appl. No.: 49,800 which a die bushing is adhesively bonded, the die bushing having one or more cavities, each of which has a punch slidably and snugly disposed therein. The punches are collectively ac- [52] US. Cl ..425/78, 425/345, 425/414 tuated by a common punch support which is in turn carried by [51 .....B30b 11/02, B30b 1 H06 a pair of posts extending below the die plate to permit recipro- [58] Field of Search 18/16 F, 16 R, 16.5, 16.7 cal movement of the punches within their respective die cavities. A plurality of core rods are provided, with each punch 56] References Ci d having one end of at least one core rod disposed within a longitudinal bore formed in each punch, while the other end of UNITED STATES PATENTS said core rod is fixedly mounted on a core rod support, which in turn is fixedly mounted to the posts below the punch sup- 3,132,379 5/1964 Crane ....18/16.5 Port Means disposed below the core rod Support and amen? 3328840 7/1967 vfnson F ing therethrough are operatively connected to the punch supzf port to selectively cause reciprocation thereof. inson 3,561,054 2/1971 Smith ..18/16 F 37 Claims, 17 Drawing Figures 20 /6 /Z 67 22 N 8 a PAIENTEIIFEB a ma 3.640.654

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saw u or 5 INVENTOR JOSEPH E.SMlTH aa-n nys DIE AND PUNCH ASSEMBLY FOR COMPACTING POWDER AND METHOD OF ASSEMBLY BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to powder compacting presses, and more particularly to an improved die and punch assembly for use in such presses, such an assembly having means providing an accurate alignment of die cavities, punches and core rods to permit a quick assembly thereof; and means permitting the use of one die plate and other common parts for accommodating the manufacture of various sizes and configurations of pressed powder articles.

2. Description of the Prior Art The present invention is an improvement over an apparatus of the character provided as part of the powder compacting press disclosed in US. Pat. No. 3,328,840, 3,344,213, 3,328,842, and 3,414,940. The powder compacting presses described and claimed in the aforementioned patents consist generally of a machine for the purpose of manufacturing memory cores, beads, pellets, tablets and the like made of a powdered ferrite, glass, alumina, metal powders, pharmaceutical, and other powder substances capable of forming a substantially solid article upon the application of a pressure in a confined molding cavity. The primary purpose of such presses is the manufacture of computer memory cores, porous bearings and bushings, transistor headers, substrates for microcircuits, and the like. Such computer memory cores, porous bearings and bushings and the like may have a toroidal, cylindrical, square or rectangular shape which often require a high degree of dimensional control. For instance, ferrite memory cores have dimensions ranging from approximately 0.005 to 0.015 inch in thickness and from approximately 0.005 to 0.025 inch in diameter, and the tolerance of these dimensions normally must be held within one-tenth of onethousandth of an inch. In addition to dimensional control, the density of compacted articles of this character, such as memory cores, must be held accurate, thereby making it necessary that the amount of powder pressed in each die cavity of the press must be substantially the same and must be repetitively maintained within extremely close limits. The finished density of all finished cores must be the same, that is, they must be uniform; accordingly the compressing of the powder material must be exact and repeatedly constant. If these dimensional and density specifications are not held within the specified tolerances, the playback level from the cores in the computer memory bank will not be substantially constant from core to core. In order to realize acceptable dimensional tolerances, it is necessary that the compacting press be capable of accurate adjustment of the movements of several component parts within at least 25 to 50 one-millionths of an inch, and that precautions be taken to insure correct fill of each die cavity.

In the preferred embodiment of the powder compacting presses as disclosed in several of the aforementioned patents, the articles are compacted and formed in a multicavity die. Finished articles are automatically ejected from the die, picked up by a vacuum suction head, and delivered into vials or bottles. A flipper assembly, which is part of the press, is mounted movable transversely over the die plate and carries a secondary powder hopper, which is supplied with powder from a primary hopper connected thereto by means of a flexi ble tubing, is first positioned over the die cavities which are filled with the powder to overflow as the punches are displaced downwardly so as to draw into the die cavities a predetermined amount of powder. The hopper is vibrated to aid in filling each die cavity. The hopper is removed while wiping the die plate surface clean from excess powder and replaced by the anvil which in turn is clamped in position on the upper surface of the die and over the die cavities.

The powder in each die cavity is then compacted against the anvil by means of the punches. The anvil is removed from the position over the die cavities and replaced by the vacuum pickup head. The punches are then raised so as to bring their upper ends substantially flush with the surface of the die plate, so that the finish compacted articles are ejected from the die cavities and picked up by the vacuum pickup head. The vacuum pickup head is then moved from over the die cavities and disposed over a series of apertures arranged in a disposition similar to the arrangement of the die cavities in the die, and the finished articles are dropped through the apertures into separate vials or bottles.

In the US. Pat. to Vinson No. 3,328,840, the preferred die and punch assembly for forming an article of a desired shape comprised a die plate having a plurality of equal angularly spaced bores arranged in a circle, a punch associated with each of the bores and adapted to be displaced in the bore to form a cavity for the powder between the top of the punch and the surface of the die plate and a core rod associated with each of the punches and axially slidable in a longitudinal bore in the punch. During the compacting cycle of the aforementioned Vinson patent, the core rod would be displaced upwardly in the cavity so that its head would be flush with the surface of the die plate and the powder disposed around the core rod would be compressed by the punch moving toward the anvil disposed over the cavity. Thus, the movement of both the core rods and the punch would have to be precisely controlled during each cycle. In certain of the aforementioned patents, an improvement was provided in that each of the core rods were adjusted to be flush with the upper surface of the die plate and then held stationary in a position during operation of the compacting press, while the punches were displaced axially in the cavities in a regular cycle to form the compact toroidal shaped article. This was an improvement over the original patents, in that only a single movable member was required in the die cavity, and thus requiring less control and insuring a more accurate dimensional control.

Although the die and punch assembly disclosed in the aforementioned patents have functioned in a very acceptable manner, the present invention provides an improved die and punch assembly which eliminates certain disadvantages associated with such high production automatic powder compacting presses. For example, in the powder compacting presses described in the aforementioned patents, a die plate is used having a plurality of die bushings each fonning its own cavity, and because of the aforementioned close dimensional tolerance requirement, such die plates and die bushings are very expensive to manufacture.

Further, since each die plate requires different sized bores to accommodate varying sized bushings, standardization of the die plates in such powder compacting presses cannot be achieved.

In the aforementioned powder compacting presses, it is necessary to provide proper angular alignment between the die cavities, the punches, punch support, core rod support, the core rods and the actuating mechanism which causes relative reciprocating motion between the punches and the die cavities, all of which necessitates the mounting of these components in an enclosed housing. The use of such an enclosed housing makes cleaning and lubrication of the several com ponents contained therein very difficult during the operation of the apparatus.

Another problem associated with the high production automatic powder compacting presses of the character described is the maintenance of a high degree of surface finish of the various members exposed to the powder and associated with dimensional tolerances of the finished article. Some of the powder substances, for instance the powder ferrite hereinbefore mentioned used in the formation of computer memory cores, have highly abrasive properties. Thus, the various components and particularly the upper surface of the die plate tends to wear and become rounded as the upper assembly which traverses the die plate sweeps the excess powder ferrite from the surface of the die plate prior to moving the anvil into engagement with the filled cavities. This sweeping action tends to wear the die plate so that acceptable dimensional tolerances are gradually lost. When this happens, the die plate must be replaced. Replacement of the die plate and reassembly thereof to provide for accurate alignment of the several components is a time-consuming operation as performed in the existing aforementioned die and punch assemblies and thus the downtime of the machine is considerable, resulting in an increase in the ultimate cost of manufacturing such powder articles.

It would therefore be desirable to provide a die and punch assembly for use in the powder compacting presses of the type hereinbefore described which has all of the advantages of such previously described die and punch assemblies, but without any of the hereinbefore described disadvantages.

SUMMARY OF THE INVENTION The present invention, which will be described subsequently in greater detail, comprises a die and punch assembly for a powder compacting press having a die plate with a die bushing aperture adapted to receive a single-die bushing having one or more cavities, the single-die bushing being retained within the die plate aperture by means of a bonding adhesive. Each die cavity has a punch slidably disposed therein, the punches in turn being collectively actuated by a punch support which, in turn, is slidably mounted between a pair of posts extending downwardly from the die plate and attached thereto proximate the die plate aperture. Core rods, if used, extend through longitudinal bores within each punch and are fixedly mounted to a core rod support which, in turn, is fixedly attached to the post at a position below the punch support. Means disposed below the core rod support and operatively connected to the punch support cause selected reciprocal movement thereof. The several examples of die and punch assembly, incorporating features of the present invention as disclosed herein, are adapted to reduce the time and effort involved in the assembly of a die plate, die bushings, punches, and the core rods by providing a unique mounting arrangement which permits the die and punch assembly to be quickly assembled in a manner which permits perfect angular alignment of the various components.

It is therefore an object of the present invention to provide a die and punch assembly for use with a powder compacting press constructed to insure a more reliable and reparative control of dimensional tolerances; which permits standardization of the die plate, die bushings, punches, punch support, core rods and core rod support; which is less expensive in its construction than existing die and punch assemblies, and which obviates the other disadvantages hereinbefore described.

It is also an object of the present invention to provide a die plate, die bushings, punches, punch support, core rods and a core rod support having a bonded construction eliminating the need for threaded and flanged connections or the fabrication of parts from a large single piece of material, all of which substantially reduces fabrication costs and permits the standardization of the components of the die and punch assembly, while accommodating variations in the punch and core rod designs which permit the use of shoulders, flanges and related clamping devices for affixing these components when necessary. The bonded construction of the die and punch assembly permits the use of a clearance space between the several components, allowing for an unconstrained, stress free alignment of all components and reducing the close tolerance required by press fits and other mechanical methods of assembly, and thus substantially reducing manufacturing costs. The bonded construction of the present invention completely eliminates any relative movement between the punches and the punch supports such as disclosed in the aforementioned patents, resulting in the maintenance of a precise relationship from punch to punch in the die and punch assembly and to the movements of the punch support as the same moves from an eject position; to a fill position; to a press position, and thus insuring a more precise control over the weight and size of the articles produced by the die and punch assembly.

It is also an object of the present invention to provide a die and punch assembly in which the die bushing is so designed as to permit an unconstructed layout of a maximum number of cavities in the die bushing and the punch support is likewise not limited in number or configuration of punches so as to match the layout of the die bushing.

It is still another object of the present invention to provide a die and punch assembly having a punch support mounted in such a manner that it will not exert any angular and/or rotating forces on the punches and thus will not bind or break small and fragile punches as the punch support reciprocates the punches during a compacting operation.

Other objects, advantages, and applications of the present invention will become apparent to those skilled in the art of powder compacting presses when the description of some examples of the best modes contemplated for practicing the invention is read in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS The description herein makes reference to the accompanying drawings wherein like reference numerals refer to like parts and in which:

FIG. 1 represents a schematic cross-sectional view of a die and punch assembly constructed in accordance with the present invention and including a hopper disposed over the die cavities, and with the die cavities filled with a powder substance;

FIG. 2 is a view of the die and punch assembly illustrated in FIG. 1 shown in the press position;

FIG. 3 is an enlarged fragmentary cross-sectional view of a modification of the core rod mounting means illustrated in FIG. 1;

FIG. 4 represents a schematic cross-sectional view of another example of a die and punch assembly constructed in accordance with the present invention shown in the die cavity filled position and taken on line 44 of FIG. 5;

FIG. 5 is a fragmentary cross-sectional view of the die and punch assembly shown in FIG. 4 and taken on line 5-5 thereof;

FIG. 6 is a fragmentary cross-sectional view of the die and punch assembly illustrated in FIG. 4 with the assembly shown in the press position and taken along line 6-6 of FIG. 5;

FIG. 7 is a cross-sectional view of the die and punch assembly illustrated in FIG. 4 with the assembly shown in the press position;

FIG. 8 represents a schematic cross-sectional view of another example of a die and punch assembly constructed in accordance with the present invention, the assembly being shown in the die cavity filled position;

FIG. 9 is a top plane view of the die and punch assembly illustrated in FIG. 8 as seen generally from line 99 of FIG. 8;

FIG. 10 is a fragmentary cross-sectional view of the die and punch assembly illustrated in FIG. 8 and taken generally along lines 10l0 thereof;

FIG. 1 l is a fragmentary exploded view of the die and punch assembly illustrated in FIG. 1 showing the method of assembly of the die bushing, punches and punch support to the die plate; and

FIG. 12 represents a schematic cross-sectional view of another example of a die and punch assembly with the assembly shown in the press position and taken along line I2- 12 of FIG. 12a;

FIG. 12a is a top plan view of the die and punch assembly illustrated in FIG. 12 as seen generally from line Ila-12a of FIG. 12;

FIG. 13 represents a schematic cross-sectional view of another example of a die and punch assembly illustrating a modified construction for mounting the punches to the punch support;

FIG. 14 represents a schematic cross-sectional view of another example of a die and punch assembly similar to the die and punch assembly illustrated in FIG. 4 with a modification to the punch and core rod mounting means;

FIG. represents a schematic cross-sectional view of another example of a die and punch assembly similar to the die and punch assembly illustrated in FIG. 9 with a modification to the punch and core rod mounting means;

FIG. 16 is a fragmentary cross-sectional view of a die and punch assembly similar to the die and punch assembly of FIG. 15 illustrating another modification to the core rod mounting means.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawings and in particular to FIGS. 1 and 2, there is shown an example of the present invention in the form of a die and punch assembly 10 having a die plate 12 adapted to be seated in a counterbore 14 of a table 16, which in turn forms a portion of a powder compacting press (not shown).

The die plate 12 preferably has a flat upper surface and is held to the upper surface of the table 16 by any suitable means (not shown), such as clamps, screws or the like. The die plate 12 is provided with a cylindrically shaped aperture 18 formed about an axis 20 which is disposed normally to the upper surface of the die plate 12. A cylindrically shaped die bushing 22, preferably formed of a hard material such as a carbide, is retained within the aperture 18 by a suitable adhesive material disposed between the outer periphery of the die bushing 22 and the surface of the aperture 18. The manner in which the die bushing 22 is inserted within the apertures 18 and the preferred type of adhesive will be described in greater detail hereinafter. As can be seen from FIGS. 1 and 2, the die bush ing 22 is inserted in the aperture 18 such that the upper surface of the die bushing is flush with the upper surface of the die plate 12.

The die bushing 22 is provided with a plurality of mutually parallel bores 24 disposed in a circular arrangement around the axis 20 and having a regular peripheral spacing; each of the parallel bores 24 extends normally downwardly from the upper face of the die bushing 22 and is provided with a chamfered portion 26 at the lower end thereof.

The die plate 12 is further provided with a pair of longitudinal bores 28 and 30 radially spaced from the axis 20 by predetermined equal distances. Associated with each bore 28 and 30 there is one of a pair of downwardly extending support posts 32 and 34, respectively. The support posts 32 and 34 are of an elongated cylindrical shape and are retained within the bores 28 and 30 by any suitable adhesive or otherwise fastened into the bores such as by a press-fit assembly or by means of setscrews.

The die and punch assembly 10 further comprises a core rod support 36 of a generally cylindrical shape. The core rod support 36 is provided with a plurality of mutually parallel bores 38 disposed in a circular arrangement around the axis 20, having a regular peripheral spacing similar to the die bushing bores 24. The core rod support 36 is further provided with a centrally disposed bore 40 formed about the axis 20 and in which a tubular member 42 is disposed. Tubular member 42 has an inner bearing surface 43 in which an actuating stem 44 is slidably mounted. The upper portion of the tubular member 42 has an enlarged portion 46, the lower surface of which is in abutment with the upper surface of the core rod support 36. The lower portion of the tubular sleeve 42 extends below the core rod support 36 and has a threaded surface 48 formed thereon which is engaged by a retaining nut 50,.

The core rod support 36 is also provided with a pair of Iongitudinal bores 52 and 54 which are radially spaced from the axis 20 by the same distance as the die plate bores 28 and 30. The core rod support 36 is positioned at a selected distance from the bottom surface of the die bushing 22 by means of a sliding engagement between the bores 52 and 54 and the support posts 32 and 34, respectively. A pair of threaded passages 56 and 58 radially extend from the outer periphery of the core rod support 36 and respectively terminate at the bores 52 and 54, the threaded passages 56 and 58 accommodating set screws 60. The cylindrically shaped core rod support 36 may be adjusted up and down the support post 32 and 34 at a selected distance from the lower surface of the die bushing 22 and then locked in place by means of the setscrews 60.

The die and punch assembly 10 includes a punch support 62 which is provided with a plurality of mutually parallel bores 64 disposed in circular arrangement about the axis 20 and having a regular peripheral spacing such that when the punch support 62 is carried by the post 32 and 34, as will be described hereinafter, the peripheral spacing of the bores 64 and the peripheral spacing of the core rod support bores 38 are such that the respective bores are in axial alignment. Each of the bores 64 is provided with an elongated cylindrical punch 66 which extends axially upwardly from the punch support 62 to register with the die bushing bores 24 which are in axial alignment therewith. The outer diameter of each of the punches 66 accurately fits the inner diameter of each of the die bushing bores 24 to define die cavities 67. Each punch 66 has a longitudinal bore 68 closely fitting the outer diameter of a core rod 70 which is disposed within the longitudinal bore 68 for relative slidable movement such that each punch 66 is slidably guided over each core rod 70. The punches 66 are free for up and down movement relative to the core rods 70. Each punch 66 has an enlarged intermediate portion 72, the lower surface of which abuts the upper surface of the punch support 62 to aid in transmitting the upwardly directed force from the actuating stem 44 to a powdered material 92 within the die cavities 67, as will be described in greater detail hereinafter. The lower ends of the punches 66 are preferably retained within the bores 64 by a suitable adhesive.

The punch support 62 is provided with a longitudinal bore 74, the axis of which coincides with the axis 20. The bore 74 is adapted to receive a decreased diameter end portion 75 of the actuating stem 44, the same being retained within the bore 74 by any suitable adhesive.

The punch support 62 has a pair of radially spaced longitudinal bores 76 and 78, respectively, adapted to slidably engage the support posts 32 and 34 and thus upon reciprocating motion of the actuating stem 44, the punch support 62 will move toward and away from the die bushing 22 in a sliding relationship with respect to the support posts 32 and 34, whereby the hereinbefore described registering of the elongated cylindrical punches 66 with the die bushing bores 24 is achieved.

Each of the core rod support bores 38 receives a sleeve insert 80 having a lower enlarged portion 81, the upper surface of which abuts the bottom surface of the core rod support 36 so as to limit the upwardly movement of the sleeves 80 within the bores 38. Each of the sleeve inserts 80 is provided with an axially extending longitudinal bore 82 having a diameter closely fitting each core rod 70 which is adapted to be disposed therein. Each of the elongated core rods 70 has an enlarged lower end 84 which abuts the lower end portion of the sleeve insert 80 to limit the upward movement of the core rod 70 into the sleeve insert bore 82. A washer 86 disposed on the upper surface of the retaining nut 50 collectively engages the lower surfaces of the enlarged portions 84, and thus as the retaining nut 50 is tightened on the tubular member 42, it exerts a clamping action against the enlarged portions 84 of the core rods 70 clamping the same in place, while at the same time clamping the sleeve inserts 80 in abutment with the lower surface of the core rod support 36.

Each core rod 70 has a diameter corresponding to that of the central bore of a toroidally shaped article, and has a length such that the upper end thereof may be disposed flush with the upper surface of the die bushing 22, so as to not interfere with the movement of a hopper 88 and an anvil 90.

Referring to FIG. 3 for a description of a modification of the sleeve insert 80, there is illustrated a sleeve insert 80' having a plurality of longitudinal bores 82 and a plurality of core rods 70 disposed therein, which in turn are adapted to be received by a punch 66 within three axially extending longitudinal bores 68' similar to the punch holes 68 to form a toroidally shaped article having more than one bore extending therethrough. Thus, it can be seen that by using different sleeve inserts 80 and 80' (all of which have an outer diameter corresponding to the bores 38) the core rod support 36 is a standard component which will not have to be changed to accommodate for the compacting of articles having a different number of bores extended therethrough. The core rods 70 used in the modification illustrated in FIG. 3 and the inserts 80' are maintained in position by the retaining nut and washer arrangement 50 and 86, respectively, in the same manner as hereinbefore described.

For purposes of illustration, a typical powder compaction cycle includes a powder filling step, a compacting step, and an ejection step. Briefly, the filling step is diagrammatically illustrated in FIG. 1 and comprises a powdered supply device, or what is commonly referred to as the hopper 88, which is disposed over the die plate 12, completely encompassing the die bushing 22, and which fills the die cavity 67 defined by the bore 24 and the upper end of the punch 66. The punches 66 are displaced a suitable distance from the upper surface of the die bushing 22 by means of the actuating stem 44; when the cavity 67 is filled with a powdered material 92, the punches 66 are then displaced slightly downwardly to draw in an amount of powder so as to insure that the cavity 67 is filled with the powder. The hopper 88 is vibrated to insure a complete filling of the die cavities. After the filling operation, the hopper 88 is removed by means not shown and the upper surface of the die bushing 22 wiped clean of any excess powder, which can be accomplished by the hopper 88 being moved transversely across the upper surface of the die bushing 22. The upper surface of the die bushing 22 is preferably polished to a superfinish so that there is no possibility of any grain of powder remaining on the surface after the wiping step. Referring to FIG. 2, the anvil 90, supported by means not shown, is transferred over the filled die cavities 67 and clamped in position, and the punch holder 62 is actuated by means of the actuating stem 44 to force the punches 66 upwardly so as to compact the powder 92 contained in the cavities 67 against the anvil 90 to form a compacted finished article. It should be noted that the outer portions of the lower surface of the anvil 90 abut against the upper surface of the die plate 12. Abutment of the anvil 90 is not limited to the upper surface of the die bushing 22 since it is smaller than the anvil 90 and thus the die bushing 22 is not loaded by the anvil 90 and is less prone to sinking in a downwardly direction during the compacting operation. The anvil 90 is then removed from over the die cavities 67 and the punches 66 are preferably displaced upwardly so that their ends are substantially flush with the upper surface of the die bushing 22 so that they eject the finished articles which may be picked up by any suitable means and removed from the cavities 67 and deposited in any suitable container such as described in the aforementioned patents.

Referring to FIG. 11 wherein there is illustrated a fragmentary exploded view of the die and punch assembly for an understanding of the manner in which the same is assembled. The assembly operation normally takes place with the die plate 12 removed from the table 16. The die plate 12 is normally disposed in a horizontal plane with its lower surface facing upwardly and with its upper surface on several sheets of paper on a fiat surface. The die bushing 22, having whatever type and number of bores 24 which may be desired formed therein, is placed in the die plate aperture 18 with a suitable adhesive disposed between the outer periphery of the die bushing 22 and the surface of the aperture 18. The adhesive is likewise applied to the port holes 28 and 30 in the die plate 12 and the support post 32 and 34 respectively positioned therein. The punches 66 are then placed in the bores 24 as partially illustrated in FIG. 11. The punch support 62 is placed on the support posts 32 and 34 and lowered over the die bushing 22 and punches 66. The die bushing 22 and the punches 66 disposed within the bores 24 are then rotated within the aperture 18 until the outer ends of the punches 66 become aligned with the bores 64 in the punch support 62 so that the punches 66 engage the bores 64 to provide for a perfect angular alignment between the bores 24, the punches 66 and the punch support bores 64, The adhesive is precured for approximately 3 minutes before the punch support 62 is removed. I

The adhesive used between the surface of the aperture 18 and the outer periphery of the die bushing 22 is of such a nature as to permit rotational movement of the die bushing 22 with respect to the aperture 18 so as to obtain a proper alignment prior to the adhesive curing. The adhesive may be a commercial quick-setting bonding compound such as an anaerobic adhesive which will securely maintain the die bushing within the aperture 18 when subjected to pressure during the compacting operation, as hereinbefore described, yet when subjected to heat will readily permit disengagement and removal of the die bushing 22 from the aperture 18. As an exemplary example, one of such bonding compounds is known and marketed under the name of Loctite" manufactured by the Loctite Corporation, Newington, Connecticut. The compound, particularly useful in the bonding of cylindrical parts, is an anaerobic adhesive having unusually high shear strength exceeding that of conventional press-fitted parts for up to five times. The Loctite retaining compound is fast curing and has excellent heat and solvent resistant characteristics, as well as providing the high shear strength between the adjoining interfaces. A more detailed description of the Loctite retaining compound may be had by reference to copending application Ser. No. 861,672 filed on Sept. 29, 1969 and which is assigned to the assignee of the present application.

Thus standardization of the die plate 12 may be had by simply using a plurality of die bushings 22 having the desired cavity sizes and configurations as is necessary, depending upon the particular type of article which is desired to be compacted. After the die bushing 22 is installed and aligned, the ends of the punches are coated with an adhesive and the punch holder is again lowered to engage the punches 66 for bonding of the punches 66 to the punch holder bores 64,

The tubular member 42 is then bonded to the core rod support 36 and the core rod support 36 placed on the support posts 32 and 34 as hereinbefore described and attached to the support posts 32 and 34 by means of the set screws 60. The actuating stem 44, which is bonded to the bore 74 of the punch support 62, is readily received through the bushing 42. The core rod sleeve inserts are inserted within their respective bores 38 and the core rods 70 (not shown in FIG. 11) are inserted therethrough and into the longitudinal bores 68 of the punches 66. The washer 86 is then placed over the enlarged portions 84 of the core rods 70 and the retaining nut 50 is screwed on the threaded portion 48 of the tubular member 42. Prior to tightening of the retaining nut 50, the core rod support set screws 60 should be loosened to allow the core rod support 36 to align itself to the core rods 70. If Locu'te is used as an adhesive, the complete assembly is placed on a hot plate and cured for 15 minutes.

Referring to FIGS. 4-7 wherein another example of the present invention is illustrated, the die and punch assembly 10 is shown with the die plate 12 having the downwardly extending support posts 32 and 34 (one of which is shown in FIG. 6) on which the core rod support 36 and the punch support 62 are respectively fixedly attached and slidably mounted in a manner similar to the aforementioned description of the example illustrated in FIGS. 1 and 2.

It may be desirable to compact a single article which is substantially larger than the articles which may be compressed within the die bushing 22 illustrated in FIG. 1, and which requires the total compacting force available from the die and punch assembly 10. To achieve this, the die bushing 22 is replaced with a die bushing 100. The die bushing 100 has a centrally disposed bore 102 extending normally inwardly from the upper face of the die bushing [00 and is provided with a charnfered portion 104 at the lower end thereof. A single die punch 66 is carried by the punch support 62 in a bore 106 which is centrally disposed in the punch support 62 in axial alignment with the die bushing bore 102. The die cavity 102 and the single-die punch 66 may take any desired peripheral configuration, such as a cylindrical or square shape. The punch 66 has a longitudinal bore 68 which slidably and snugly receives the core rod 70, which in turn is held by the core rod support 36 while the punch 66 is bonded to the bore 106 in a similar manner as hereinbefore described in the description of the embodiment illustrated in FIG. 1. A sleeve insert, similar to the sleeve insert 80, may be used with the single punch 66 to form an article having more than one bore extending therethrough.

Since the punch 66 is centrally disposed on the punch support 62, the actuating stem 44 of FIG. 1 may not be utilized to directly reciprocate the punch 66 as the lower end of the punch 66 and the upper end of the actuating stem 44 would have to occupy the same location. In order to overcome this difficulty, a lower punch support 108 is provided at the upper end of the actuating stem 44 and in the present embodiment is formed integrally therewith. The lower punch support 108 has a pair of apertures, one of which is shown in FIG. 6 at 110, which slidably engages the stem posts 32 and 34 to guide the support 108 during reciprocal movement thereof and to maintain the lower support 108 in proper axial alignment with the upper punch support 62. The lower punch support 108 is connected to the upper punch support 62 by a pair of threaded fasteners 112 which extend axially upwardly through a bore 114 in the lower punch support 108 and threadingly engage the punch support 62 at 116. A sleeve member 118 surrounds each fastener 112, the upper and lower surfaces of the sleeve member 118 being respectively in abutment with the lower and upper surfaces of the punch supports 62 and 108. Thus, as the fasteners 112 are threaded into the punch support 62, the supports 62 and 108 are fixedly secured to one another and reciprocate as a unit under the motion of the actuating stem 44. Bores 120, disposed in the core rod support 36, slidably receive the outer periphery of the sleeve members 118. The fasteners 112 are angularly displaced from the support posts 32 and 34 and, as can be seen in FIG. 5, the fasteners 112 are angularly disposed 90. from the support posts 32 and 34.

The core rod support 36 is further provided with a central bore 124 in which a sleeve element 126 having a central bore 128 is bonded. The sleeve element 126 has an enlarged upper end 129 which abuts the upper surface of the core rod support 36 to limit the downward movement of the sleeve member 126 into the core rod support bore 124. The lower end of the sleeve element 126 extends below the lower surface of the core rod support 36 and is provided with a threaded surface 130 which is threadingly engaged by a cup-shaped retaining nut 132. The sleeve insert 80 with the core rod 70 extending therethrough is inserted into the sleeve element bore 128 and retained therein by means of the cup-shaped retaining nut 132 which engages the enlarged portion 84 of the core rod 70 in a clamping engagement.

Reference is now made to FIGS. 8, 9 and 10 for an understanding of another example of the present invention. In certain applications it may be desirable to have a die bushing provided with a cluster of die bores as the die bushing 140 H lustrated in FIG. 9 is provided with a plurality of die bores 142. Each of the die bores 142 has a punch 66 associated therewith to form die cavities 144. The punches 66 are carried by the punch support 62, which in turn slidably engages the downwardly extending support posts 32 and 34 in a manner similar to the embodiments disclosed in FIGS. 1 and 4. Associated with each punch 66 is a core rod 70 slidably disposed in the punch bores 68, the lower ends of the core rods being fixedly mounted to the core rod support 36, which, in turn, is fixedly mounted to the support posts 32 and 34 by the setscrews 60. Below the core rod support 36, there is provided the lower punch support 108' which slidably engages the posts 32 and 34 in the same manner as the punch support 108 functions, as described in the description of the embodiment in FIG. 4. The lower punch support 108 is connected to the upper punch support 36 by means of the threaded fasteners 112', as illustrated in FIG. 10, the construction of which is similar to the fasteners 112 illustrated in FIG. 4. The lower punch support 108' has a threaded centrally disposed bore which threadingly engages a threaded end 146 formed on the upper end of the actuating stem 44. However, the lower punch support 108 may be formed integrally with the stem 44 as is illustrated in FIG. 4.

The core rod support 36 is provided with a plurality of bores 148, each of which is in axial alignment with the die bores 142. Each bore 148 is adapted to receive the sleeve insert 80 which is retained therein by any suitable means, such as the adhesive Loctite hereinbefore described. The lower enlarged ends 84 of each core rod 70 are retained in place by the clamping action of a washer 150 and a clamping plate 152 which are clamped to the core rod support 36 by threaded fasteners 154. The threaded fasteners 1S4 extend through bore 156 in the plate 152 and threadingly engage threaded bores 158 within the core rod support 36.

Referring now to FIGS. 12 and 12a, the die and punch assembly 10 is shown with the die plate having a die bushing 200 adhesively bonded within the die plate aperture 18. The die bushing 200 is provided with a plurality of die bores 202 having cylindrical punches 204 snugly and slidably disposed therewithin to form the die cavities. The punches 204 are carried by a punch support 206 which, in turn, slidably engages the pair of downwardly extending support posts 32 and 34 in a manner similar to the embodiment disclosed in FIG. 4. Since the embodiment illustrated in FIGS. 12 and 12a does not incorporate core rods, a core rod support is not required. Below the punch support 206 there is provided a lower punch support 208 which slidably engages the support posts 32 and 34 in the same manner as the punch support 108 functions as described hereinbefore in the description of the embodiment illustrated in FIG. 4. The lower punch support 208 is connected to the upper punch support 206 by means of threaded fasteners 210, the construction of which is similar to the fasteners 112 described hereinbefore. The lower punch sup' port 208 has a centrally disposed bore 212 which received a reduced diameter end 214 fonned on the upper portion of the actuating stem 44, however, the lower punch support 208 may be formed integrally with the stem 44.

The punch support 206 has a central aperture 216 including an upper annular seat 218 which receives a punch insert 220 having an annular lip 222 which engages the annular seat 218 to prevent downward movement of the inert 220 into the punch support bore 216. A suitable adhesive, such as Loctite is applied to the outer surface of the insert 220 and the inner surface of the bore 216 to secure the insert 220 to the punch support 206. The punch insert 220 is provided with a plurality of parallel bores 224 disposed in a circular arrangement about its longitudinal axis and having a regular peripheral spacing; each of the bores 224 being in axial alignment with the die bushing bores 202. The bores 224 receive the lower end of the punches 204. The punch 204 has an enlarged intermediate portion 226, the lower surface of which abuts the upper surface of the punch insert 220 to aid in transmitting the upper directed force of the actuating stem 44 to the powdered material within the die cavities in a manner similar to the intermediate portions 72 described hereinbefore in the description of the embodiment illustrated in FIGS. 1 and 4. It can be seen that by using the punch support 206 any combination and number of punches 204 may be accommodated simply by providing a different punch insert 220 and a mating die bushing 200, thereby standardizing the punch support 206.

Referring to FIG. 13 wherein there is illustrated a modification of the punches 204 and the punch insert 220. The punches 204' illustrated in FIG. 13 are of a cylindrical shape with the enlarged intermediate portions 226 being eliminated. The ends of punches 204' are received in a punch insert 230 having a plurality of parallel bores 231 that are axially aligned with bores 232 in a die bushing 234 adhesively held within the die plate 12. The punch insert 230 and the punches 204' are supported by a cup-shaped support member 236 having an outer periphery complementary to the bore 216 and step 218 of the punch support 206. A suitable adhesive such as Loctite is applied between the outer periphery of each punch 204 and the inner periphery of the insert bores 231 to secure the punches 204 therein, while the cup-shaped support member 236 is bonded to punch support 206, all of which will be described in greater detail hereinafter in the description of assembling die and punch illustrated in FIGS. 12 through 16. The cup-shaped support member 236 replaces the enlarged intermediate portions 226 and acts to transmit the upwardly directed force from the actuating stem 44 through the punch 204' to compact the powder material in the die cavities in the die bushing 234. Downward movement of the punches 204 is prevented by abutment with the bottom interior wall 238 of the cup-shaped support member 236.

FIG. 14 illustrates the die and punch assembly as having a die bushing 240 with a centrally disposed bore 242 in which a punch 244 is slidably and snugly disposed. The lower extended end of the punch 244 is received by a centrally disposed bore 246 formed in a punch insert 248 which, in turn, is supported by a cup-shaped support member 250 similar to the insert support member 236 illustrated in FIG. 13. The die and punch assembly of FIG. 14 is further provided with a core rod support 252 fixedly mounted to the support posts 32 and 34 by means of setscrews 60 in the same manner as the core rod supports described hereinbefore are mounted. The core rod support 252 is provided with a central aperture 254 in which a core rod insert 256 is bonded by a suitable adhesive. The punch has a longitudinal bore 258 closely fitting the outer diameter of a core rod 260 which is disposed therewithin for relative slidable movement such that the punch 244 is slidably guided over the core rod 260. The core rod 260 extends through a centrally disposed aperture 262 in the cup-shaped support member 250 and is fixedly mounted in a bore 264 within the insert 256 by any suitable means such as the adhesive Loctite.

FIG. 15 illustrates a die and punch assembly similar to the die and punch assembly illustrated in FIG. 14 and in which a plurality of punches 244 and core rods 260 are provided, the punches 244 being mounted by a cup-shaped support 250 and the punch insert 248 in a similar manner, while the core rods 260 are bonded to a plurality of axially aligned core rod bores 264 in the core rod insert 256.

FIG. 16 is a fragmentary view of a die and punch assembly similar to the die and punch assembly disclosed in FIG. 15 in which a cup-shaped support member 266 is used to support a cylindrically shaped core rod insert 268. The construction of the cup-shaped support member 266 supporting the core rod insert 268 is identical to the construction of the cup-shaped support member 250 supporting the punch insert 248, thus permitting standardization of yet another component of the present invention.

To assembly the die and punch assemblies illustrated in FIGS. 12-16, a suitable adhesive such as Loctite7 is applied to the die plate aperture 18 and post apertures 28 and 30 in the die plate 12. The die plate 12 is disposed on a horizontal surface with its lower face facing upwardly and its upper surface disposed on several sheets of paper. Loctite is applied to the outer periphery of the die bushing, which in turn is placed into the die bushing aperture 18 of the die plate 12. A suitable centerline mark 270 (FIG. 12a may be placed on the bottom surfaces of the die bushing and die plate to permit a proper orientation between the die bushing and the die plate. Loctite" is then applied to the support posts 32 and 34 which, in turn, are installed in the post apertures 28 and 30 within the die plate 12. The punch support 206, core rod support 252 (if used) and lower punch support 208 are positioned on the support post 32 and 34 to obtain a perfect alignment of the post 32 and 34 with the punch support 206, core rod support 252, and the lower punch support 208. The adhesive is precured for approximately three minutes and the supports 206, 252 and 208 are removed from the support post 32 and 34.

The punches are then placed in the die bushing bores and Loctite is applied to the extended end portions of each punch and to the bores of the punch inserts. The punch inserts are then placed over the ends of the punches so that the punches protrude slightly through the insert. Loctite" is then applied to the outer periphery of the punch insert and the inner surface of the cup-shaped punch support member. The cup-shaped punch support member is positioned over the punch insert, contacting the end of the punches, and the core rod bores in the punch support member are aligned with core rod bores of the punches if the core rods are so used. The ends of the punches are pressed firmly until the bonding material sets (approximately 30 seconds). The cushioning effect of the several sheets of paper disposed on the top side of the die plate under the punches will compensate for slight variations in the length of the punches. Loctite" is then applied to the outer surface of the cup-shaped punch support member and the inner surface of the punch support 206 which, in turn, is lowered over the support posts until it engages and is supported by the cup-shaped support member. If the assembly includes core rods, the same are installed. The core rod support 252 is positioned on the support posts and lowered below the ends of the core rods. Loctite is applied to the core rod bores and the outer surface of the core rod insert which, in turn, is lowered over the ends of the core rods until they stick slightly through the opposite end of the core rod insert. The core rod support 252 is raised until it engages and supports the core rod insert. If a cup-shaped core rod insert support member 266 is used as disclosed in FIG. 16, the same is positioned on the core rod insert prior to the positioning of the core rod support 252 on the support post 32 and 34. After the core rod support has engaged the core rod insert (or the cupshaped core rod insert support member 266, if used) the core rod support is locked in place on the support post 32 and 34 by means of the setscrews 60. Each core rod is punched to insure contact with the paper below the top face of the die plate 12.

The entire assembly is then placed on a hot plate and the adhesive is cured for approximately l5 minutes, whereupon the die and punch assembly 10 is ready for finish grinding and lapping of the punch, core rod ends, the die plate, and the die bushing at the top face end of the die plate 12.

It can therefore be seen that the present invention has provided several examples of a die and punch assembly for use in a powder compacting press constructed in a manner to insure a more reliable and repetitive control of the dimensional tolerances; which permits the fabrication of varying sized articles with the use of the same die plate; which has eliminated the outer housing used in the hereinbefore described die and punch assemblies; and which has eliminated the other disadvantages hereinbefore described.

While the form of the several examples of the invention as herein disclosed constitute preferred forms, it is to be understood that other forms might be adopted, all coming within the spirit of the invention and the scope of the appended claims.'

What is claimed is as follows:

1. A compacting apparatus for making articles compacted from a powder substance comprising: a die plate; an aperture in the die plate; a die bushing fixedly fastened in the aperture in said die plate; at least one die cavity in said bushing; a punch having an end engaged in one end of said die cavity and reciprocable therewithin; a pair of guide posts affixed to said die plate; a punch support connected to the other end of said punch and slidably engaging said guide posts for reciprocating movement relative to said die bushing, said punch support and said guide posts cooperating to provide axial alignment between said punch and said die cavity; a longitudinal bore extending in said punch from said one end to said other end thereof; a core rod slidably and snugly disposed within said punch longitudinal bore and having an end projecting through said other end of said punch and said punch support; a core rod support fixedly mounted to said posts below said punch support and having means for mounting said core rod on said core rod support for axial alignment with said punch bore; and reciprocating means positioned below said core rod support and operatively connected to said punch support for reciprocating said punch support relatively to said die bushing,

2. The compacting apparatus defined in claim 1 further comprising an aperture in said core rod support; and a support insert fixedly mounted in said core rod support aperture and having means of mounting the core rod projecting end.

3. The compacting apparatus defined in claim 2 wherein said core rod support aperture has a step formed on the die bushing facing side; said apparatus further comprising a cupshaped member having an outer periphery contoured to mate with said core rod support aperture and including a lip portion abutting said step portion, said support insert being mounted in the interior of said cup-shaped member.

4. The compacting apparatus defined in claim 3 wherein said support insert has a bore extending from one end to the other end thereof, said core rod extending through said last mentioned bore, with the projecting end of said core rod abutting the bottom interior wall of said cup-shaped member.

5. The compacting apparatus defined in claim 1 further comprising a plurality of substantially circularly arranged die cavities in said die bushing, each of said die cavities being shaped as a cylindrical bore opened at both ends, a plurality of punches, each having an end engaged in one end of each of said die cavities and reciprocable therewithin, each of said punches snugly fitting within each of said die cavities; said punch support being connected to the other ends of said punches and reciprocable therewith for providing axial alignment between said punches and their associated die cavities; each of said punches having a longitudinal bore extending from said one end to said other end thereof; a plurality of core rods each slidably and snugly disposed within each of said punch bores, each of said core rods having an end projecting through the other end of its associate punch and said punch support, and said projecting ends mounted to said core rod support for axial alignment with their associated punch bores.

6. The compacting apparatus defined in claim 5 further comprising an aperture in said core rod support, a support insert fixedly mounted in said core rod support aperture and having a step fonned on the die bushing facing side; a cupshaped member having an outer periphery contoured to mate with said core rod support aperture and including a lip portion abutting said step portion; a support insert fixedly mounted in the interior of said cup-shaped member, said support insert having a plurality of parallel bores in axial alignment with said punch longitudinal bores, the extending ends of said core rods being disposed in said support insert bores, said projecting ends of said core rods abutting the bottom interior of said cupshaped member.

7. The compacting apparatus defined in claim 6 further comprising an aperture in said punch support, said aperture having a step formed on the die bushing facing side; a second cup-shaped member having an outer periphery contoured to mate with said punch support aperture and including a lip portion abutting said punch support step portion; a second support insert fixedly mounted in the interior of said second cupshaped member, said second support insert having a plurality of parallel bores extending from one end to the other end thereof, said last-mentioned bores being axially aligned with said die cylindrical bores, said other ends of said punches being disposed in said second support insert bores, said other end of said punches abutting the bottom interior wall of said second cup-shaped member; said second cup-shaped member having a plurality of parallel bores extending from one end to the other end of said bottom wall through which said extending ends of said core rods extend.

8. The compacting apparatus as defined in claim 5 wherein said reciprocating means comprises an actuating stern slidably disposed within a bore extending through said core rod support, said actuating stern having one end projecting upwardly through said core rod support and being operatively connected to said punch support.

9. The compacting apparatus as defined in claim 5, further comprising a plurality of substantially circularly arranged apertures in said core rod support, a plurality of sleeve inserts, each disposed in each of said plurality of support apertures. an enlarged portion on said projecting end of each of said core rods, said core rods projecting through said sleeve inserts and restrained from upward movement toward said die bushing by means of an abutment of said enlarged portion with said sleeve insert; and means abutting said enlarged portions for preventing movement of said core rods away from said die bushing.

10. The compacting apparatus as defined in claim 9 wherein said core rod support comprises an aperture centrally disposed with respect to said circularly arranged first mentioned support apertures, said apparatus further comprising a sleeve member, the interior of which forms a bearing surface, said sleeve member having one end thereof projecting downwardly from said core rod support; means carried by the other portion of said extended sleeve member for clampingly engaging the bottom portion of said enlarged end portion of said core rods for preventing movement of said core rods away from said die bushing; and, said actuating stern being slidably mounted in said sleeve interior and extending from opposite ends thereof, the upward end of said actuating stem engaging said punch support to impart reciprocal movement thereon as said actuating stem is reciprocated within said sleeve interior.

11. The compacting apparatus as defined in claim 10, further comprising a threaded surface formed on said extended portion of said sleeve member; and a retaining nut threadingly received by said threaded portion, the upper surface of said retaining nut engaging said enlarged portion of said core rods to clamp the same against said sleeve inserts.

12. The compacting apparatus as defined in claim 1 wherein said die bushing is releasably attached within said die plate aperture.

13. The compacting apparatus as defined in claim 12 wherein said die bushing is retained within said die plate aperture by means of a bonding agent disposed between the other surface of said die bushing and the surface of said die plate aperture.

14, The compacting apparatus as defined in claim 1 further comprising a plurality of longitudinal bores extending from said one end to said other end of said punch; a plurality of core rods each slidably and snugly disposed within each of said longitudinal bores and each having an end projecting through the other end of said punch and said punch support; said core rod support having an aperture extending from end to end therein; a sleeve insert disposed in said core rod support aperture, said sleeve insert having a plurality of longitudinal bores axially aligned with said punch longitudinal bores; each of said core rods extending through said sleeve insert elongated bores, said core rods each having an enlarged end portion abutting the lower side of said sleeve insert to prevent upward movement of said core rods toward said die bushing; and means abutting the underside of said enlarged portions in a clamping relationship to prevent movement of said core rods downwardly away from said die bushing.

15. The compacting apparatus as defined in claim 14, further comprising a plurality of substantially circularly arranged die cavities and a plurality of punches associated with said die cavities 16. The compacting apparatus as defined in claim 1 wherein said die cavity is centrally disposed with respect to the outer periphery of said die bushing; said punch being centrally disposed with respect to the outer periphery of said die support, said die support maintaining said punch in axial alignment with said die cavity.

17. The compacting apparatus as defined in claim 16, further comprising a second punch support disposed below said core rod support, said second punch support slidably engaging said posts for reciprocal movement relative to said die plate; and including means operatively connecting said second punch support to said first-mentioned punch support, said connecting means being angularly displaced from said posts.

18. The compacting apparatus as defined in claim 17 wherein said last-mentioned connecting means comprises a pair of upwardly extending connecting rods passing through apertures formed in said core rod support and operatively connecting said second punch support with said first punch support; said reciprocating means being operatively connected to said second punch support to cause reciprocal movement thereof.

19. The compacting apparatus as defined in claim 18 wherein said connecting members are angularly displaced 90R.

from said posts.

20. The compacting apparatus as defined in claim 18 wherein each of said connecting rods comprise a screw extending through one of said punch supports and threadingly engaging the other of said punch supports, a bearing sleeve disposed around said screw intermediate the lower surface of said first punch support and the upper surface of said second punch support whereby engagement of said screws into said other punch support fixedly secures said punch supports to one another; the outer periphery of said bearing sleeves extending through bores in said core rod support in a sliding engagement.

21. The compacting apparatus defined in claim 16, further comprising a sleeve insert centrally disposed in an aperture formed in said core rod support, said sleeve insert having a longitudinal bore extending from end to end thereof, said core rod extending through said sleeve insert bore and having an enlarged end portion, the inner side of which abuts said sleeve insert to prevent upward movement of said core rod toward said die bushing, and, including means abutting the lower end of said enlarged portion to prevent downward movement of said core rod away from said die bushing.

22. The compacting apparatus defined in claim 21, further comprising an aperture centrally disposed in said core rod support, a sleeve member having an enlarged upper portion in abutment with the upper portion of said core rod support, the lower portion of said sleeve member extending beyond the lower portion of said core rod support, said sleeve member having an aperture therein and in which said sleeve insert is fixedly disposed, the lower outer surface of said sleeve member having a threaded surface; and a cup-shaped member having an internal threaded surface adapted to engage said sleeve member threaded surface for simultaneously clamping the lower surface of said enlarged sleeve portion against the upper surface of said core rod support and for clampingly engaging the lower side of said enlarged portion of said core rod to prevent downward movement of said core rod with respect to said die bushing.

23. The compacting apparatus defined in claim 16 wherein said die bushing is releasably attached within said die plate aperture.

24. The compacting apparatus defined in claim 21 wherein said die bushing is retained within said die plate by means of a bonding agent disposed between the outer periphery of said die bushing and the surface of said die plate aperture.

25. The compacting apparatus defined in claim 1, furthe comprising a cluster of vertically disposed die cavities in said die bushing, each shaped as a cylindrical bore opened at both ends; a plurality of punches each having an end engaged in one end of said plurality of cavities and reciprocal therewith, the other ends of said punches being connected to said punch support and reciprocal therewith, said punch support maintaining said punches in axial alignment with their respective die cavities, a lower second punch holder support disposed below said core rod support, and including means operatively connecting said lower punch support to said first-mentioned punch support, said connecting means being angularly displaced from said posts.

26. The compacting apparatus defined in claim 25 wherein said connecting means are angularly disposed at a position 90 displaced from said posts.

27. The compacting apparatus defined in claim 26 wherein said connecting means comprises a threaded fastener extending through one of said punch supports and threadingly engaging the other of said punch supports; a bearing sleeve disposed around said threaded fastener intermediate said upper and lower punch supports, said threaded member clamping said upper and lower punch supports against the opposite ends of said bearing sleeve.

28. The compacting apparatus defined in claim 25 wherein each of said punches has a longitudinal bore extending from said one end to said other end of said punch; a plurality of core rod members each slidably and snugly disposed within said longitudinal bores of said punches and each having an end projecting through said other end of said punches and said first punch support; said core rod support having a plurality of apertures in axial alignment with said die cavities; said apparatus further comprising a plurality of sleeve inserts disposed in said last-mentioned apertures, each of said sleeve inserts having a longitudinal bore extending from end to end; said projecting ends of said core rods being disposed in said sleeve insert bores, said core rods having enlarged ends, the upper portion of which abuts the bottom portion of said sleeve inserts to prevent upward movement of said core rods with respect to said bushing; and means clampingly engaging the lower ends of said enlarged ends of said core rods to prevent movement of said core rods away from said die bushing.

29. The compacting apparatus defined in claim 28 wherein said last-mentioned clamping means comprises a plate in abutment with said plurality of enlarged core rods; and including fastening means extending through portions of said plate into said core rod support for holding said plate in said clamping engagement with said enlarged end portions.

30. The compacting apparatus defined in claim 25 wherein said die bushing is releasably attached within said die plate aperture.

31. The compacting apparatus defined in claim 30 wherein said last-mentioned means comprises a bonding adhesive disposed between the outer periphery of said die bushing and the inner surface of said die plate mounting aperture.

32. A compacting apparatus for making articles compacted from a powder substance comprising: a die plate; an aperture in the die plate; a die bushing fixedly fastened in the aperture in said die plate; at least one die cavity in said bushing; a punch having an end engaged in one end of said die cavity and reciprocal therewithin; a pair of guide posts affixed to said die plate; a punch support connected to the other end of said punch and slidably engaging said guide posts for reciprocating movement relative to said die bushing, and for providing axial alignment between said punch and said die cavity; reciprocating means positioned below said punch support and operatively connected to said punch support for reciprocating said punch support relative to said die bushing.

33. The compacting apparatus defined in claim 32, further comprising an aperture in said punch support; and a support insert fixedly mounted in said punch support aperture and having means for mounting the other end of said punch.

34. The compacting apparatus defined in claim 33, further comprising an aperture in said support insert, said other end of said punch extending into said support insert aperture; said punch having an enlarged portion abutting the top of said support insert for preventing relative inward movement of said punch into said support insert aperture.

35. The compacting apparatus defined in claim 33 wherein said said punch support aperture has a step formed on the die bushing facing side; said apparatus further comprising a cup shaped member having an outer periphery contoured to mate with said punch support aperture and including a lip portion abutting said step portion, said support insert being mounted in the interior of said cup-shaped member.

36. The compacting apparatus defined in claim 35 wherein said support insert has a bore extending from one end to the other end thereof, said punch being disposed in said last mentioned bore, said other end of said punch abutting the bottom interior wall of said cup-shaped member.

PEN ll4 A UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Dated February 8, 1972 Patent No. 3 640, 654

Inventor(s) JOSEPH E SMITH It is certified that error appears in the above-identified patent atent are hereby corrected as shown below:

and the; said Lctccis I IN THE SPECIFICATION Column 6,- line 75, change "holes" to bores Column 11, line 55, change "assembly" to assemble IN THE CLAIMS Column 13, line 10, change "of" to for Signed and sealed this 13th day of June 1972.

(SEAL) Attest:

ROBERT GOTTSCHALK USCOMM-DC 503764 69 Q ".5. GOVERNMENT PRINTING OF'ICE: I969 0-366-3Jl FORM PO-IOSO (10-69) 

1. A compacting apparatus for making articles compacted from a powder substance comprising: a die plate; an aperture in the die plate; a die bushing fixedly fastened in the aperture in said die plate; at least one die cavity in said bushing; a punch having an end engaged in one end of said die cavity and reciprocable therewithin; a pair of guide posts affixed to said die plate; a punch support connected to the other end of said punch and slidably engaging said guide posts for reciprocating movement relative to said die bushing, said punch support and said guide posts cooperating to provide axial Alignment between said punch and said die cavity; a longitudinal bore extending in said punch from said one end to said other end thereof; a core rod slidably and snugly disposed within said punch longitudinal bore and having an end projecting through said other end of said punch and said punch support; a core rod support fixedly mounted to said posts below said punch support and having means for mounting said core rod on said core rod support for axial alignment with said punch bore; and reciprocating means positioned below said core rod support and operatively connected to said punch support for reciprocating said punch support relatively to said die bushing.
 2. The compacting apparatus defined in claim 1 further comprising an aperture in said core rod support; and a support insert fixedly mounted in said core rod support aperture and having means for mounting the core rod projecting end.
 3. The compacting apparatus defined in claim 2 wherein said core rod support aperture has a step formed on the die bushing facing side; said apparatus further comprising a cup-shaped member having an outer periphery contoured to mate with said core rod support aperture and including a lip portion abutting said step portion, said support insert being mounted in the interior of said cup-shaped member.
 4. The compacting apparatus defined in claim 3 wherein said support insert has a bore extending from one end to the other end thereof, said core rod extending through said last mentioned bore, with the projecting end of said core rod abutting the bottom interior wall of said cup-shaped member.
 5. The compacting apparatus defined in claim 1 further comprising a plurality of substantially circularly arranged die cavities in said die bushing, each of said die cavities being shaped as a cylindrical bore opened at both ends, a plurality of punches, each having an end engaged in one end of each of said die cavities and reciprocable therewithin, each of said punches snugly fitting within each of said die cavities; said punch support being connected to the other ends of said punches and reciprocable therewith for providing axial alignment between said punches and their associated die cavities; each of said punches having a longitudinal bore extending from said one end to said other end thereof; a plurality of core rods each slidably and snugly disposed within each of said punch bores, each of said core rods having an end projecting through the other end of its associate punch and said punch support, and said projecting ends mounted to said core rod support for axial alignment with their associated punch bores.
 6. The compacting apparatus defined in claim 5 further comprising an aperture in said core rod support, a support insert fixedly mounted in said core rod support aperture and having a step formed on the die bushing facing side; a cup-shaped member having an outer periphery contoured to mate with said core rod support aperture and including a lip portion abutting said step portion; a support insert fixedly mounted in the interior of said cup-shaped member, said support insert having a plurality of parallel bores in axial alignment with said punch longitudinal bores, the extending ends of said core rods being disposed in said support insert bores, said projecting ends of said core rods abutting the bottom interior of said cup-shaped member.
 7. The compacting apparatus defined in claim 6 further comprising an aperture in said punch support, said aperture having a step formed on the die bushing facing side; a second cup-shaped member having an outer periphery contoured to mate with said punch support aperture and including a lip portion abutting said punch support step portion; a second support insert fixedly mounted in the interior of said second cup-shaped member, said second support insert having a plurality of parallel bores extending from one end to the other end thereof, said last-mentioned bores being axially aligned with said die cylindrical bores, said other ends of said punches being disposed in said second support insert bores, said other end of said punches abutting the bottom interior wall of said second cup-shaped member; said second cup-shaped member having a plurality of parallel bores extending from one end to the other end of said bottom wall through which said extending ends of said core rods extend.
 8. The compacting apparatus as defined in claim 5 wherein said reciprocating means comprises an actuating stem slidably disposed within a bore extending through said core rod support, said actuating stem having one end projecting upwardly through said core rod support and being operatively connected to said punch support.
 9. The compacting apparatus as defined in claim 5, further comprising a plurality of substantially circularly arranged apertures in said core rod support, a plurality of sleeve inserts, each disposed in each of said plurality of support apertures, an enlarged portion on said projecting end of each of said core rods, said core rods projecting through said sleeve inserts and restrained from upward movement toward said die bushing by means of an abutment of said enlarged portion with said sleeve insert; and means abutting said enlarged portions for preventing movement of said core rods away from said die bushing.
 10. The compacting apparatus as defined in claim 9 wherein said core rod support comprises an aperture centrally disposed with respect to said circularly arranged first mentioned support apertures, said apparatus further comprising a sleeve member, the interior of which forms a bearing surface, said sleeve member having one end thereof projecting downwardly from said core rod support; means carried by the other portion of said extended sleeve member for clampingly engaging the bottom portion of said enlarged end portion of said core rods for preventing movement of said core rods away from said die bushing; and, said actuating stem being slidably mounted in said sleeve interior and extending from opposite ends thereof, the upward end of said actuating stem engaging said punch support to impart reciprocal movement thereon as said actuating stem is reciprocated within said sleeve interior.
 11. The compacting apparatus as defined in claim 10, further comprising a threaded surface formed on said extended portion of said sleeve member; and a retaining nut threadingly received by said threaded portion, the upper surface of said retaining nut engaging said enlarged portion of said core rods to clamp the same against said sleeve inserts.
 12. The compacting apparatus as defined in claim 1 wherein said die bushing is releasably attached within said die plate aperture.
 13. The compacting apparatus as defined in claim 12 wherein said die bushing is retained within said die plate aperture by means of a bonding agent disposed between the other surface of said die bushing and the surface of said die plate aperture.
 14. The compacting apparatus as defined in claim 1 further comprising a plurality of longitudinal bores extending from said one end to said other end of said punch; a plurality of core rods each slidably and snugly disposed within each of said longitudinal bores and each having an end projecting through the other end of said punch and said punch support; said core rod support having an aperture extending from end to end therein; a sleeve insert disposed in said core rod support aperture, said sleeve insert having a plurality of longitudinal bores axially aligned with said punch longitudinal bores; each of said core rods extending through said sleeve insert elongated bores, said core rods each having an enlarged end portion abutting the lower side of said sleeve insert to prevent upward movement of said core rods toward said die bushing; and means abutting the underside of said enlarged portions in a clamping relationship to prevent movement of said core rods downwardly away from said die bushing.
 15. The compacting apparatus as defined in claim 14, further comprising a plurality of substAntially circularly arranged die cavities and a plurality of punches associated with said die cavities.
 16. The compacting apparatus as defined in claim 1 wherein said die cavity is centrally disposed with respect to the outer periphery of said die bushing; said punch being centrally disposed with respect to the outer periphery of said die support, said die support maintaining said punch in axial alignment with said die cavity.
 17. The compacting apparatus as defined in claim 16, further comprising a second punch support disposed below said core rod support, said second punch support slidably engaging said posts for reciprocal movement relative to said die plate; and including means operatively connecting said second punch support to said first-mentioned punch support, said connecting means being angularly displaced from said posts.
 18. The compacting apparatus as defined in claim 17 wherein said last-mentioned connecting means comprises a pair of upwardly extending connecting rods passing through apertures formed in said core rod support and operatively connecting said second punch support with said first punch support; said reciprocating means being operatively connected to said second punch support to cause reciprocal movement thereof.
 19. The compacting apparatus as defined in claim 18 wherein said connecting members are angularly displaced 90* from said posts.
 20. The compacting apparatus as defined in claim 18 wherein each of said connecting rods comprise a screw extending through one of said punch supports and threadingly engaging the other of said punch supports, a bearing sleeve disposed around said screw intermediate the lower surface of said first punch support and the upper surface of said second punch support whereby engagement of said screws into said other punch support fixedly secures said punch supports to one another; the outer periphery of said bearing sleeves extending through bores in said core rod support in a sliding engagement.
 21. The compacting apparatus defined in claim 16, further comprising a sleeve insert centrally disposed in an aperture formed in said core rod support, said sleeve insert having a longitudinal bore extending from end to end thereof, said core rod extending through said sleeve insert bore and having an enlarged end portion, the inner side of which abuts said sleeve insert to prevent upward movement of said core rod toward said die bushing, and, including means abutting the lower end of said enlarged portion to prevent downward movement of said core rod away from said die bushing.
 22. The compacting apparatus defined in claim 21, further comprising an aperture centrally disposed in said core rod support, a sleeve member having an enlarged upper portion in abutment with the upper portion of said core rod support, the lower portion of said sleeve member extending beyond the lower portion of said core rod support, said sleeve member having an aperture therein and in which said sleeve insert is fixedly disposed, the lower outer surface of said sleeve member having a threaded surface; and a cup-shaped member having an internal threaded surface adapted to engage said sleeve member threaded surface for simultaneously clamping the lower surface of said enlarged sleeve portion against the upper surface of said core rod support and for clampingly engaging the lower side of said enlarged portion of said core rod to prevent downward movement of said core rod with respect to said die bushing.
 23. The compacting apparatus defined in claim 16 wherein said die bushing is releasably attached within said die plate aperture.
 24. The compacting apparatus defined in claim 21 wherein said die bushing is retained within said die plate by means of a bonding agent disposed between the outer periphery of said die bushing and the surface of said die plate aperture.
 25. The compacting apparatus defined in claim 1, further comprising a cluster of vertically disposed die cavities in said die bushing, each shaped as a cylindrical bore opened at both ends; a plurality of punches each having an end engaged in one end of said plurality of cavities and reciprocal therewith, the other ends of said punches being connected to said punch support and reciprocal therewith, said punch support maintaining said punches in axial alignment with their respective die cavities, a lower second punch holder support disposed below said core rod support, and including means operatively connecting said lower punch support to said first-mentioned punch support, said connecting means being angularly displaced from said posts.
 26. The compacting apparatus defined in claim 25 wherein said connecting means are angularly disposed at a position 90* displaced from said posts.
 27. The compacting apparatus defined in claim 26 wherein said connecting means comprises a threaded fastener extending through one of said punch supports and threadingly engaging the other of said punch supports; a bearing sleeve disposed around said threaded fastener intermediate said upper and lower punch supports, said threaded member clamping said upper and lower punch supports against the opposite ends of said bearing sleeve.
 28. The compacting apparatus defined in claim 25 wherein each of said punches has a longitudinal bore extending from said one end to said other end of said punch; a plurality of core rod members each slidably and snugly disposed within said longitudinal bores of said punches and each having an end projecting through said other end of said punches and said first punch support; said core rod support having a plurality of apertures in axial alignment with said die cavities; said apparatus further comprising a plurality of sleeve inserts disposed in said last-mentioned apertures, each of said sleeve inserts having a longitudinal bore extending from end to end; said projecting ends of said core rods being disposed in said sleeve insert bores, said core rods having enlarged ends, the upper portion of which abuts the bottom portion of said sleeve inserts to prevent upward movement of said core rods with respect to said bushing; and means clampingly engaging the lower ends of said enlarged ends of said core rods to prevent movement of said core rods away from said die bushing.
 29. The compacting apparatus defined in claim 28 wherein said last-mentioned clamping means comprises a plate in abutment with said plurality of enlarged core rods; and including fastening means extending through portions of said plate into said core rod support for holding said plate in said clamping engagement with said enlarged end portions.
 30. The compacting apparatus defined in claim 25 wherein said die bushing is releasably attached within said die plate aperture.
 31. The compacting apparatus defined in claim 30 wherein said last-mentioned means comprises a bonding adhesive disposed between the outer periphery of said die bushing and the inner surface of said die plate mounting aperture.
 32. A compacting apparatus for making articles compacted from a powder substance comprising: a die plate; an aperture in the die plate; a die bushing fixedly fastened in the aperture in said die plate; at least one die cavity in said bushing; a punch having an end engaged in one end of said die cavity and reciprocal therewithin; a pair of guide posts affixed to said die plate; a punch support connected to the other end of said punch and slidably engaging said guide posts for reciprocating movement relative to said die bushing, and for providing axial alignment between said punch and said die cavity; reciprocating means positioned below said punch support and operatively connected to said punch support for reciprocating said punch support relative to said die bushing.
 33. The compacting apparatus defined in claim 32, further comprising an aperture in said punch support; and a support insert fixedly mounted in said punch support aperture and having means for mounting the other end of said punch.
 34. The compacting apparatus Defined in claim 33, further comprising an aperture in said support insert, said other end of said punch extending into said support insert aperture; said punch having an enlarged portion abutting the top of said support insert for preventing relative inward movement of said punch into said support insert aperture.
 35. The compacting apparatus defined in claim 33 wherein said said punch support aperture has a step formed on the die bushing facing side; said apparatus further comprising a cup-shaped member having an outer periphery contoured to mate with said punch support aperture and including a lip portion abutting said step portion, said support insert being mounted in the interior of said cup-shaped member.
 36. The compacting apparatus defined in claim 35 wherein said support insert has a bore extending from one end to the other end thereof, said punch being disposed in said last mentioned bore, said other end of said punch abutting the bottom interior wall of said cup-shaped member.
 37. The compacting apparatus defined in claim 36, further comprising a plurality of parallel bores in said die bushing, each of said bores accommodating a punch for relative slidable movement, said support insert having a plurality of parallel bores respectively axially aligned with said die bushing bores, said support insert bores receiving said other ends of said punches, said other ends abutting the bottom interior wall of said cup-shaped member. 